1. Technical Field
The present invention generally relates to acoustical transducers and manufacturing methods thereof. More particularly, the present invention relates to damper and bobbin assemblies of loudspeakers.
2. Related Art
A loudspeaker is essentially a transducer for converting electrical energy to acoustic energy, and is universally known and utilized in audio systems. There are a wide variety of designs employing various operational principles, and can be generally categorized as electrodynamic, electrostatic, piezoelectric, or discharge speakers, among others. The most common type of loudspeaker is of the electrodynamic variety, in which an electrical signal representative of the desired audio is applied to a voice coil suspended between opposite poles of a magnet and attached to a semi-rigid cone. The voice coil interacts with the magnet by the generated electromagnetic force, and causes the coil and the semi-rigid cone to vibrate and reproduce the frequencies present in the electrical signal.
Conventional loudspeaker designs typically include a T-yoke, which defines an annular slot or air gap for receiving a bobbin having a voice coil. As will be readily recognized, the bobbin is a hollow cylindrical member configured to enable a sliding relation with the T-yoke, particularly within the annular slot. The T-yoke is typically cylindrical in shape and holds a magnet that is positioned in alignment with the voice coil on the bobbin. Placed above the magnet is a top plate, which connects the yoke and the magnet to a basket. The basket serves as an attachment and securing point for the surround, which is an annular flexible member that holds a cone-shaped diaphragm having a central opening. The bobbin is attached to the central opening of the diaphragm, and the opening of the bobbin is covered by a dust cap to reinforce the structural integrity of the diaphragm. Lateral and axial stability of the bobbin, and thus the diaphragm, is enhanced by a damper. The damper is typically a ring-shaped member having an interior edge glued to the bobbin and an exterior edge glued to the basket. In this regard, the damper resiliently supports the diaphragm and bobbin at the respective predetermined static positions within the air gap without contacting the surrounding surfaces of the yoke or the magnet.
One inherent deficiency in prior loudspeaker designs was that the power output of the loudspeaker was directly related to the number of turns in the voice coil, and consequently, the size of the voice coil was related to the size of the loudspeaker. Few alterations attempting to overcome these proportion-related deficiencies have been contemplated. In order to accommodate a greater number of turns, it was necessary for the height of the bobbin to be increased for a given width of the magnet and the yoke cooperating therewith. However, by increasing the height of the bobbin, the vertical position of the voice coil which is electromagnetically driven is deviated from the vertical position of the interior edge of the damper. This destabilized the bobbin and the diaphragm, resulting in what is referred to in the art as “rolling,” thereby causing the voice coil to rub against the magnet or the yoke and resulting in distorted audio and damage to the voice coil. Therefore, under conventional loudspeaker designs, there was a ceiling of which no greater power output was possible without increases in size. Therefore, an alternative loudspeaker overcoming the aforementioned deficiencies would be desirable.